A. 0.5
B. 1
C. 3.5
D. 9.05
Related Mcqs:
- For existence of aquatic life in water, the dissolved oxygen content in it, should not be less than ______________ ppm?
A. 10000
B. 5
C. 500
D. 1000 - The concentration of water vapour in troposphere, which depends upon the altitude & temperature, varies in the range of zero to ______________ percent?
A. 1
B. 4
C. 8
D. 12 - Dissolved oxygen content in river water is around _____________ ppm?
A. 5
B. 100
C. 250
D. 500 - ______________ content of the phosphate rock is the pollutant of primary interest in a phosphatic fertiliser plant ?
A. Calcium
B. Fluorine
C. Phosphorous
D. Sulphur - Disinfection of water is done to destroy pathogenic bacteria and thus prevent water-borne diseases. Disinfection of water may be done by the use of_________________?
A. Ozone and iodine
B. Chlorine or its compounds
C. Ultraviolet light for irradiation of water
D. All A., B. & C. - The destruction of water-borne pathogens is termed as disinfection of water. Which of the following is a water disinfectant ?
A. Chlorine
B. Alkalis
C. Benzene hexachloride
D. Alkyl benzene sulphonate (ABS) - The amount of chemical coagulant added for treatment of polluted water ______________ with increase in temperature of the polluted water to be treated?
A. Decreases
B. Increases
C. Remain constant
D. May increase or decrease; depends on the chemical characteristics of polluted water - Acute danger to human life (i.e. death) exists, if the concentration of CO2 in atmospheric air exceeds ______________ percent (by volume)?
A. 1
B. 3
C. 7
D. 20 - During which of the following operating conditions of an automobile, carbon monoxide content in the exhaust gas is maximum ?
A. Idle running
B. Acceleration
C. Cruising
D. Deceleration - In water treatment plant, zeolite process is used to remove the _____________ of water?
A. Acidity
B. Alkalinity
C. Hardness
D. Iron & zinc
